Vibration detector



FIG. 1 is a perspective view of a vibration detector showing our invention;

FIG. 2 is a side elevational view thereof, this side and each of the other sides being of identical designs;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof. 

The ornamental design for a vibration detector, as shown and described. 